As the youth mentoring field has expanded and diversified in America over the last 30-plus years, many adults who care about getting these valuable relationships to more young people have asked questions about the scope and scale of mentoring in American society. In 2014, MENTOR first started to examine these societal level trends in a seminal research study that resulted in a report called "The Mentoring Effect," a first-of-its-kind attempt to capture the prevalence of both program-provided and naturally occurring mentoring relationships for America's youth. Needless to say, this research was highly illuminating as to who in society was receiving mentoring, what they were getting out of those relationships, and where there were critical gaps that needed filling. The years since that report have seen tremendous turmoil and changes in American life. Thus, MENTOR thought that the time was right to take a fresh look at some of these topics and to dig a bit deeper into the mentoring relationships that young people experience and the ways in which those relationships supported personal development and growth. MENTOR launched this research project with four core goals in mind: (1) Taking a fresh look at the mentoring "gap"; (2) Creating understanding about the growth of the mentoring movement over time; (3) Deepening the understanding of the value of mentoring on all American lives; and (4) Examining the things mentors do that young people find valuable. [This report was produced with Pacific Market Research. Funding for this report was provided by EY. For the Executive Summary, see ED626844. For "The Mentoring Effect: Young People's Perspectives on the Outcomes and Availability of Mentoring. A Report for Mentor: The National Mentoring Partnership," see ED558065.]